Recently, as a base station device (referred to as a base station) in a wireless communication system, a home cell has been proposed as well as a macrocell of related art which has a wide service area. The home cell is designed to provide services in a narrow area and, in some cases, services dedicated for specific users. Operation of the home cell has been considered for 3GPP E-UTRA (The 3rd Generation Partnership Project Evolved Universal Terrestrial Radio Access) (see, for example, Non-Patent Document 1).
Currently, as methods of controlling an access between a base station of a home cell (referred to as a home cell base station) and a mobile station device (referred to as a mobile station), the three following methods have been proposed. The first method is an open access method. The second method is a hybrid access method. The third method is a closed access method. Regarding the open access method, any mobile station can access the home cell base station, as in the case of a macrocell. Additionally, regarding the hybrid access method, not only mobile stations subscribing to a CSG (Closed Subscriber Group; a group of specific subscribers, such as employees in a corporation, users in an institution, or family members in a home), but also mobile stations not subscribing to the CSG, can access the home cell base station. Further, regarding the closed access method, only mobile stations subscribing to the CSG can access the home cell base station.
On the other hand, the use of the home cell during roaming has been considered. In other words, a mobile station accesses a home cell base station in a VPLMN (Visited Public Land Mobile Network) in some cases. For this reason, it is expected that the opportunity for a mobile station not subscribing to the CSG to access the home cell base station will increase.
The section 5.3.1 of Non-Patent Document 1 discloses that a mobile station subscribing to the CSG performs manual CSG selection, thereby a CSG membership being offered to another mobile station camping on the VPLMN cell. Here, the CSG membership is offered without exchange of information related to the HPLMN and the CSG of the other mobile station.